The technology of the present disclosure relates to an optical scanning device that forms a latent image on a surface to be scanned by exposure scanning, and an image forming apparatus including the same such as a copy machine, a printer, a facsimile, and a multifunctional peripheral thereof.
Conventionally, in an optical scanning device used in an image forming apparatus, beam light emitted from a light source is deflected in a deflector such as a polygon mirror, is led to a photosensitive drum (an image carrying member) by passing through an optical member such as a lens, exposes and scans a surface of the photosensitive drum, and forms an electrostatic latent image thereon.
In such an optical scanning device, a sensor for detecting writing light is arranged in order to decide a writing position (a writing timing) of an image. A writing position is controlled such that after the writing light is incident into the detection sensor, an image is written after a predetermined time (several μseconds) passes. The writing light is reflected toward the detection sensor by a mirror. However, at this time, when an angle of the mirror in a sub-scanning direction is shifted, since the writing light is deviated in a vertical direction (the sub-scanning direction) of the detection sensor and is not detected, drawing is not started.
Conventionally, in order to correct a position of the writing light in the sub-scanning direction, a correcting lens is mounted. However, since the correcting lens is expensive as compared with general resin parts, it is preferable to employ a configuration with no correcting lens in order to enhance a cost-down effect by reducing parts. Therefore, particularly, when an optical path length from the mirror to the detection sensor is long, since the accuracy of a mirror angle has a large influence on shift of the writing light in the sub-scanning direction, there is a case in which a means for adjusting the mirror angle is necessary.
In this regard, there has been known various technologies for adjusting the mirror angle with a simple configuration. For example, there has been proposed a configuration for adjusting the mirror angle by allowing one end of the mirror to be brought into press-contact with a support point of a housing side by an elastic member and to directly press the other end of the mirror by an adjusting screw.
Furthermore, for example, there has been proposed a configuration for adjusting the mirror angle by mounting the mirror in a wedge-shaped mirror holding member and rotating the mirror holding member.